Vitriums are very beautiful companions. Many people compare them to stained glass, and think of them as living art. These companions come in two different color variations. One is a pale white, which is ideal for blending in with snow. They are also unaffected by the cold and move about as usual. They're so light that they don't sink into snow, but rather walk about on top of it. They are known around the castle as jareen vitriums. The other color vitrium is a vibrant green, which allows them to frolic about in the fields without being seen. Green vitriums, or sayos vitriums, also have pink and blue colors on their wings which they disguise by hiding among flowers. They sleep inside flowers, rather than building homes as other adult creatures do. As they age, vitrium hatchlings grow into their wings and learn to fly. Adult vitriums are able to remain airborne for a short amount of time. They usually only fly when it's absolutely necessary, as they can hop great distances. When they do fly, their wings make a soft chiming noise that draws attention to them. As hatchlings, they spend most of their time outside, hunting for tidbits to eat or playing with one another. As they age, though, they develop other interests. When not enjoying the sun, or moving through the grass, adult vitrium companions like to remain inside. They find high vantage points where they won't get stepped on and watch as people create art. They most seem to enjoy watching art classes, and if you're drawing something, it's not unlikely that a vitrium is watching you.

Although they are very small and look much like insects, virtriums are actually made out of glass. If you hold one up to the light, you can see the sun shining through. These companions cannot drown, do not feel the cold, and do not need to eat. Sometimes, they'll eat a bit of glass, but mostly they seem content to lie on a blade of grass and let the sun warm them up. The only thing they seem truly fearful of is hot fires, particularly forges. They dislike dragons above all other creatures, and remain far away from them. Strangely enough, these insects get along very well with alicantos. Many were concerned when vitriums first came to the castle, alarmed that the alicantos, with their penchant for eating strange materials, would consider vitriums delicious treats. Instead, though, the two often hang out on the same tree branch, and vitriums have even been seen hitching a ride on an alicanto. Other than this odd friendship, vitriums keep their distance from most creatures because they are so delicate. The only way they survive even one day without breaking is because they are incredibly nimble. If anyone walks near them, vitriums simply jump very high to evade any danger. In addition to their fast reactions, the glass they are made out of is much stronger than normal glass.